Anti-TPO antibodies are autoantibodies that target thyroid peroxidase (TPO), an enzyme crucial for thyroid hormone synthesis. TPO is a membrane-bound hemoprotein that catalyzes the iodination of tyrosine residues and the oxidative coupling of two tyrosine residues to thyroglobulin, essential steps in thyroid hormone production.
Clinical Significance
- Anti-TPO antibodies indicate autoimmune thyroiditis, including:
- Hashimoto’s thyroiditis
- Graves' disease (diffuse toxic goiter)
- Anti-TPO antibodies contribute to thyroid cell destruction, leading to hypothyroidism or, in some cases, thyroid dysfunction.
- Take the test at least 2 hours after the last meal.
- Avoid smoking for 3 hours before the test.
- Avoid physical and emotional stress for 1 hour before the test.
This test is recommended if a patient experiences:
- Infertility
- Menstrual irregularities
- Skin issues (dry skin)
- Swelling of the face, eyelids, hands, or feet
- Hair loss and brittle nails
- Chronic fatigue or hyperactivity
- Unexplained weight gain or loss
- Depression, anxiety, or nervousness
- Cognitive issues (memory and attention problems)
- Muscle weakness or cramps
- Heat or cold intolerance
- Bloating and digestive issues
- Tachycardia (rapid heartbeat)
- Sleep disturbances and night sweats
- Low libido
- Hyperprolactinemia
Interpretation of Elevated Anti-TPO Levels
Increased Anti-TPO levels may indicate:
- Autoimmune thyroid diseases:
- Hashimoto’s thyroiditis (most common)
- Graves' disease (Basedow's disease, diffuse toxic goiter)
- Postpartum thyroiditis
- Idiopathic hypothyroidism
- Subclinical thyroid dysfunction
- Other autoimmune diseases:
- Rheumatoid arthritis
- Systemic lupus erythematosus (SLE)
- Type 1 diabetes
- Pernicious anemia